I feel like folks like you practically get off to making bad faith arguments about how regular ass voters are "letting genocide happen" and imply that by not voting, you're doing something effective to stop it.
I have to ask, hypothetically if the Palestinian death toll increased to 60,000 under a Harris presidency, and it increased to 150,000 under a Trump presidency, would you have any preference for one administration over the other if you could go back in time, or do you believe the 90,000+ death difference is meaningless? I'd genuinely like to know your answer to this question because to me it's like telling someone there's no difference between having one leg chopped off and both legs chopped off, and then hearing from some smug person in the back saying "how about we don't chop any legs off?" like it's the idea of the century that nobody has ever thought of before.
Can you be more specific? The examples you have 1) operated on a far more localized scale and dealt with domestic politics compared to international conflict between Israel/Palestine and all the countries involved behind the scenes and 2) The Black Panthers accomplished a great deal, but their overall goals did not come to fruition in the end. Racism is still rampant in America, police brutality against black people is still largely ignored excluding the occasional major outrage (i.e. George Floyd), and the American system is about as capitalist as it gets so the BPs socialist agenda didn't take root at all.
Once Newton and Hampton were gone, so were the Black Panthers. Most leftist organizing I see is unfortunately centralized around a handful of leaders whose followers believe are irreplaceable, which IMO is not a desirable trait for anything involving continuity. Everyone dies, some earlier than others, and having no effective contingency plan is a blunder so many political movements have.
Beyond that, government surveillance is beyond what we've ever seen before. Organizing political action, especially radical political action, gets shut down faster than ever and we don't often talk about it in leftist spaces because usually all that happens is someone gets their door kicked in, arrested, charged, convicted, and basically told "we've put you through one horrible traumatic experience, think carefully if you want to go through this again". We can beat out chests and say "I'm not afraid of shit" but I think the vast majority of leftists a) haven't been in prison and b) haven't a clue about what it's like in there. Prison's no joke and frankly I completely understand why regular ass people, especially those with dependants like kids, are extremely reluctant to organize in any way that could impact their employment/ability to support their loved ones. We live in an age where cracking a joke about Trump can result in a bunch of freak Republicans doing everything they can to get you fired.